a. Field of the Invention
The present invention relates generally to a motive power system such as a gas turbine system, and more particularly it pertains to a method and an apparatus for producing a high energy gaseous fluid of high temperature and pressure which can be used as the actuator fluid of a heat engine such as a gas turbine system. Still more particularly, the present invention concerns a method and an apparatus for producing a high energy gaseous fluid substantially free of physiologically harmful substances (nitrogen oxides No.sub.x, carbon monoxide CO and hydrocarbon HC) by substantially completely combusting, in an oxygen stream, a fuel of fluid-type or fine powder-type, and along therewith by forcing, into a closed pressure-tight container intended for performing said combustion, liquidous water for substantial direct heat exchange with the heat of the combustion gas to produce steam of high temperature, high pressure and high energy.
B. Brief description of the Prior Art
In general, it has been known, in for example steam engines and steam turbine systems, to utilize steam of high temperature and high pressure as the actuator fluid for use as an industrial motive power source. Steam of high temperature and high pressure is produced usually by a steam boiler. A gas turbine system, on the other hand, is arranged to be operative so that a fluid fuel which is ejected under pressure from a nozzle is combusted under the state of being mixed with a pressurized air, and the gas mixture is ignited and combusted. The resulting high temperature, high pressure combustion gas (whose components contain, in addition to the carbon dioxide and the steam which are generated from the combustion of the fuel, since the combustion utilizes air as the oxygen source, large amounts of nitrogen N.sub.2 and nitrogen oxides NO.sub.x which is extremely harmful physiologically even when its amount is small) is blown under a high pressure onto the blades of a turbine, to convert the energy of such combustion gas into mechanical energy. In each of these prior motive power generating techniques, air is used as the oxygen source which is necessary for the combustion of the fuel as the source of heat. Almost all the industrial energy sources are obtained from combustion of a fuel which is performed in the air. The problem which is attracting the attention of the people throughout the world is the counter-measure of the air pollution caused by the combustion of fuel. When various types of fuels are combusted by the use of oxygen, the combustion gases which are exhausted from the chimneys of industrial plants, the exhaust pipes of automobiles, etc. contain, in addition to the carbon dioxide and steam which are produced from the combustion of the fuels, carbon monoxide, uncombusted fuels (mainly hydrocarbons) which are due to incomplete combustion, a large amount of nitrogen which is an inert gas and which occupies substantially 80% of air, and a small amount of nitrogen oxides (NO.sub.x). These components of the exhausted gases are called "the worst three pollution substances". The former two, i.e. carbon monoxide and hydrocarbon are large in amount. However, after various research, there have been established substantially practical counter-measures for the cleaning of these two substances. As for the control and removal of NO.sub.x which is produced in a relatively small amount but is deadly toxin, there has not yet been achieved a practical means to carry out its control and removal.
The nitrogen oxides NO.sub.x are the by-products in the exhaust gases. These nitrogen oxides are inevitably produced by the use of air which contains nitrogen in an amount about 80% of air and oxygen which is indispensable for the combustion of fuels. Accordingly, in order to eliminate NO.sub.x drastically, one can not rely on anything else but on shutting out the intervention of N.sub.2. As a means for materializing this shutting-out, it is proposed not to use air as the oxygen source necessary for combustion, but to use pure oxygen instead. By doing so, the formation of NO.sub.x can be prevented completely.
However, when a fuel is combusted in a stream of oxygen, there is obtained perfect combustion. Therefore, there will be produced a high temperature extending as high a 2000.degree. C. When, for example, acetylene is combusted alike in a gas burner intended for welding, in which acetylene is combusted in a stream of oxygen, the jet flame having a bluish white color which is produced will have a high temperature exceeding 2000.degree. C. Such a high temperature flame cannot be utilized either in an ordinary steam boiler or in a gas turbine system. The jet flame is of a directional orientation and has a small flame area (high temperature area). Accordingly, if such a burner as stated above is installed in the combustion chamber of an ordinary steam boiler, the water pipe which is to be heated is not heated throughout the entire parts or length of the pipe. Not only that, but there is the fear that the wall of the water pipe located close to the foremost end of the jet flame will be melted and broken very soon as the wall is contacted by the end of the flame. This applies in the same way to a gas turbine system. Even if some counter-measure for the above-said local limited heating by the flame is taken, it should be understood that if the burner is used in an air atmosphere as in a currently used ordinary combustion engine, there is produced a large amount of NO.sub.x due to the oxidization of nitrogen contained in the intake air which is caused by a high temperature.